Vehicle audio system for producing synthetic engine sound

ABSTRACT

An audio system for an electrically powered vehicle includes a data storage unit, a processor for accessing the data storage unit and retrieving one of pre-recorded engine sounds, pre-recorded exhaust sounds, or one or more algorithms for reproducing engine sounds and exhaust sounds, an amplifier operably connected to the processor for amplifying one of an engine sound or exhaust sound, at least one outwardly directed speaker for generating one of an engine or exhaust sound, an interface between the processor and the one or more vehicle performance sensors for sensing a vehicle performance parameter, the interface configured to receive an input from the one or more vehicle performance sensors and transmit it to the processor, wherein the processor receives the input from at least one vehicle performance sensor and varies a sound parameter of an engine sound or exhaust sound projected by the speaker based on the performance parameter.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit of U.S. Provisional Application Ser. No.61/223,643, filed Jul. 7, 2009, and entitled VEHICLE AUDIO SYSTEM FORPRODUCING SYNTHETIC ENGINE SOUND.

TECHNICAL FIELD

The following disclosure relates to a vehicle audio system forelectrically powered vehicles such as “plug-in” and hybrid vehicles, andin particular, audio systems and methods for generating synthetic engineand/or exhaust sounds.

BACKGROUND

A combination of factors including ever-increasing energy costs,environmental concerns and the development of new battery technology hasrevived interest in electrically powered automobiles. “Plug-in” typeelectric vehicles rely solely on a battery powered electric motor topropel the vehicle. In some instances, “plug-in” electric vehicles mayincorporate a small combustion engine that may be used to drive anelectric generator to power the vehicle and/or recharge the battery whenthe batteries are depleted. Hybrid electric vehicles utilize both acombustion engine and an electric motor to propel the vehicle dependingupon the vehicle's power demand under different conditions and otherfactors. Currently, electrically powered cars using “plug-in” and/orhybrid technology are available that have a driving range of 200 or moremiles per day and performance rivaling or exceeding conventionalvehicles powered with gasoline or diesel fuels. Increasing fuel costshave also driven demand for hybrid vehicles that rely on a combinationof an electric drive motor with a conventional gas or diesel engine.

One characteristic of “plug-in” electrically powered vehicles is thatthe vehicles typically generate little or no engine sounds and noexhaust sounds. Similarly, hybrid electric vehicles produce little or noengine and exhaust sounds when operated in the electric mode. However,pedestrians and drivers are familiar with the engine and exhaust soundsgenerated by conventional automobiles. The sound generated by the engineand exhaust of a conventional diesel and gasoline-powered vehicle oftenalerts pedestrians, other drivers, pets and even wild animals to theapproach of the vehicle. Further, the engine and exhaust soundsgenerated by a gasoline or diesel powered engine is appealing to a largenumber of drivers and consumers that equate the engine and exhaustsounds with power and performance.

Thus, while “plug-in” electric vehicles and hybrid vehicles may provideenvironmental, and in some instances economic benefits, the lack ofengine and exhaust sounds presents certain drawbacks. From a safetyaspect, it may be desirable to provide a means for such vehicles togenerate a sound simulating a combustion engine to alert pedestrians,other drivers and animals to the presence and/or approach of anelectrically powered vehicle. It may also be desirable to generate asound simulating a combustion engine for aesthetic reasons, e.g., toappeal to those consumers that associate the sound of combustion enginewith power and performance.

SUMMARY

In one aspect, an electrically powered passenger vehicle includes anelectric drive motor operatively coupled to one or more of the vehicle'swheels for rotating the vehicle's wheels to propel the vehicle and abattery pack for powering the electric drive motor. One or more operatorcontrols are provided for steering, braking and controlling the speed ofthe vehicle. The vehicle further includes one or more sensors formonitoring one or more performance parameters of the vehicle such asspeed, acceleration, motor load or transmission output. A data and/ormedia storage unit mounted in the vehicle includes one of pre-recordedengine sounds, pre-recorded exhaust sounds, or one or more algorithmsfor reproducing engine sounds and exhaust sounds. A processor isoperably connected to the data storage unit for accessing the datastorage unit and retrieving one of pre-recorded engine sounds,pre-recorded exhaust sounds, or one or more algorithms for reproducingengine sounds and exhaust sounds. In one embodiment, a cellulartransceiver is connected to the processor whereby the processor cancommunicate with a third party service provider to download one ofpre-recorded engine sounds, pre-recorded exhaust sounds, or one or morealgorithms for reproducing engine sounds and exhaust sounds.

An amplifier is operably connected to the processor for amplifying oneof an engine sound or exhaust sound. At least one speaker is connectedto the amplifier for projecting one of engine sounds or exhaust soundsoutside the vehicle. The processor receives an input generated by thesensor and varies a sound parameter of one of engine sounds or exhaustsounds projected by the speaker based on one or more performanceparameters of the vehicle.

In one variation, the performance parameters may include one or more ofthe speed of the vehicle, acceleration of the vehicle, deceleration ofthe vehicle, speed of the drive motor and electric current draw of thedrive motor. The sound parameters controlled with the processor mayinclude volume and frequency and may be varied in a linear or non-linearmanner based upon changes in the sensed vehicle performance parameters.In one embodiment, the electrically powered passenger vehicle includesat least one speaker oriented toward a front end of the vehicle and atleast one speaker oriented toward the rear end of the vehicle whereinthe speaker oriented toward the front of the vehicle is configured toproject engine sounds outwardly from the vehicle and the speakeroriented toward the rear of the vehicle is configured to project exhaustsounds outwardly from the vehicle.

In another aspect, a method of providing prerecorded vehicle operatingsounds or algorithms for reproducing vehicle operating sounds isdisclosed. In accordance with the method, a third party service providerreceives a transmission from a user device operated by a potentialpurchaser or user with a server connected to a public or privatecomputer network. The service provider electronically transmitsselection information to the potential purchaser or user with the serverover the public or private network, the selection information includingvehicle sound selections including engine and exhaust sounds and/or analgorithm for producing such sounds. The transmitted selectioninformation may include a prompt or otherwise enable the potentialpurchaser to preview, e.g., listen to, selected sounds. The serviceprovider may receive an electronic transmission from the user deviceoperated by the potential purchaser selecting one or more engine orexhaust sounds. If the potential purchaser or user elects to hear apreview of one or more selected sounds, the server electronicallytransmits one of a segment of a prerecorded engine or exhaust sound oran algorithm for producing an engine or exhaust sound to the user devicevia the public or private network. The user device may be permanentlymounted in a “plug-in” or hybrid vehicle or may be a hand held wirelessdevice.

If the potential customer or user elects to purchase and/or receive oneor more vehicle sound selections, the service provider receives anelectronic transmission from the user device confirming that thepotential purchaser wishes to purchase one of a selected prerecordedengine or exhaust sounds or an algorithm for producing a selected engineor exhaust sound. The service provider may then electronically transmita prompt to the user device enabling the potential purchaser to select apayment type. After receiving an electronic transmission from the userdevice indicating a selected payment type, the service provider may thenelectronically transmit a request to a third party to confirm paymentinformation received from the potential purchaser and/or to debit thepurchaser's account with the third party for the purchase price of theselected sound(s) or algorithms. If the potential purchaser has anaccount with the service provider, the potential customer's accountand/or payment may be confirmed by the third party service provider.After receiving confirmation or verification of the payment information,or confirming the purchaser's account information, the third partyservice provider may electronically transmit one of the selectedprerecorded engine or exhaust sounds or an algorithm for producing aselected engine or exhaust sound to the user device.

In one embodiment the user device is a cellular transceiver and theselection information may be a screen display. The screen displayinformation is transmitted to the potential purchaser with the serverconnected to a public or private network. The display information mayfurther include sound selections including one or more of wind sounds,road sounds and animal deterrent sounds for display on the user device.In other embodiments, the selection information may be in the form of apre-recorded audio menu.

In another aspect, an audio system for an electrically powered vehicleincludes a data storage unit including one of pre-recorded engine,exhaust, road, wind and/or animal deterrent sounds, or one or morealgorithms for reproducing such sounds. The audio system furtherincludes a processor for accessing the data storage unit and retrievingone of pre-recorded sounds, or one or more algorithms for reproducingthe sounds. The processor is operably connected to an amplifier foramplifying one or more of an engine sound, exhaust sound, wind sounds,road noise, or animal deterrent sounds. At least one outwardly directedspeaker mounted outside of the passenger compartment of the vehicle isconnected to the amplifier for reproducing a selected vehicle sound suchas an engine or exhaust sound. The audio system may include a cellulartransceiver connected to the processor such that the processor cancommunicate with a third party service provider to receive and store oneof pre-recorded engine sounds, pre-recorded exhaust sounds, or one ormore algorithms for reproducing engine sounds and exhaust sounds.

The audio system includes an interface between the processor and one ormore vehicle performance sensors for sensing a performance parameter ofthe vehicle. The interface is configured to receive an input from one ormore vehicle performance sensors and transmit it to the processor. Theprocessor receives an input generated by at least one performance sensorand varies a sound parameter of one of engine sounds, exhaust sounds orother sounds projected by the speaker based on a performance parameterof the vehicle. In one embodiment, the performance parameters includeone or more of the speed of the vehicle, acceleration of the vehicle,deceleration of the vehicle, speed of the drive motor, wheel speed andelectric current draw of the drive motor. The sound parameters mayinclude the volume and frequency of sounds generated by the audiosystem.

In one variation, the audio system includes at least one speakeroriented toward a front end of the vehicle and at least one speakeroriented toward the rear end of the vehicle. The speaker oriented towardthe front of the vehicle may be configured to project engine soundsoutwardly from the vehicle and the speaker oriented toward the rear ofthe vehicle may be configured to project exhaust sounds outwardly fromthe vehicle. In one embodiment, the front and rear speakers may bedriven on separate channels. In other embodiments, an electronic mixeror similar device may be used to separate and/or combine engine, exhaustand other sounds based on frequency.

In yet another aspect, a method of producing vehicle sounds associatedwith a combustion engine includes receiving an electronic transmissionfrom a third party service provider, the electronic transmissionincluding selection information for at least one of pre-recorded enginesounds, pre-recorded exhaust sounds, or one or more algorithms forreproducing engine sounds and exhaust sounds. After the customer or userreceives the selection information, he or she electronically transmits aselection from one of prerecorded engine sounds, pre-recorded exhaustsounds, or one or more algorithms for reproducing engine sounds andexhaust sounds. In one embodiment, the customer receives and listens toa preview of the selected engine or exhaust sounds.

In order to receive the selected engine or exhaust sounds, the customerelectronically transmits payment and/or account information to the thirdparty service provider. The customer may then receive an electronictransmission including the one or more of pre-recorded engine sounds,pre-recorded exhaust sounds, or one or more algorithms for reproducingengine sounds and exhaust sounds. The one or more of prerecorded enginesounds, pre-recorded exhaust sounds, or one or more algorithms forreproducing engine sounds and exhaust sounds are stored on a storageunit for retrieval.

The stored sounds, or algorithms for producing the sounds, may beretrieved from the storage unit with an audio system of an electricallypowered passenger vehicle to reproduce one or more of an engine sound orexhaust sound. The audio system receives an input generated by at leastone vehicle performance parameter sensor and varies a sound parameterproduced by the audio system based on the performance parameter of thevehicle. The sound parameters may include volume and frequency. Thevehicle performance parameters may include one or more of the speed ofthe vehicle, acceleration of the vehicle, deceleration of the vehicle,speed of the drive motor and amperage of the electric current drawn bythe drive motor. Road noises, wind noises and animal deterrent noisesmay also be reproduced and varied with changes in the vehicleperformance parameters.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding, reference is now made to thefollowing description taken in conjunction with the accompanyingDrawings in which:

FIG. 1 illustrates an electrically powered vehicle including an audiosystem for generating engine and/or exhaust sounds according to thedisclosure;

FIG. 2 is a schematic of an audio system and related components for usewith an electrically powered vehicle;

FIG. 3 is an exemplary screen display for selecting sounds for anelectrically powered vehicle;

FIG. 4 is a graph illustrating possible relationships between the speedof an electrically powered vehicle and engine and/or exhaust soundsgenerated with an audio system;

FIG. 5 is a graph illustrating possible relationships betweenacceleration/deceleration of an electrically powered vehicle and engineand/or exhaust sounds generated with a vehicle audio system;

FIG. 6 is a graph illustrating possible relationships between the motorspeed or vehicle speed of an electrically powered vehicle and thefrequency or pitch of engine and/or exhaust sounds generated with avehicle audio system;

FIG. 7 is a graph illustrating possible relationships between the motorspeed or vehicle speed of an electrically powered vehicle and thefrequency or pitch of engine and/or exhaust sounds generated with avehicle audio system;

FIG. 8 is a graph illustrating a pulsed or interrupted volume orfrequency of engine and/or exhaust sounds generated with a vehicle audiosystem according to the disclosure;

FIG. 9 is a schematic representation of a control consol for an audiosystem for generating engine or exhaust sounds for an electricallypowered vehicle;

FIG. 10 illustrates a method for providing engine, exhaust and othersounds for use with an electrically powered vehicle; and

FIG. 11 illustrates a method for producing engine, exhaust and othersounds with an electrically powered vehicle.

DETAILED DESCRIPTION

Referring now to the drawings, wherein like reference numbers are usedherein to designate like elements throughout, the various views andembodiments of a vehicle audio system for producing synthetic enginesound are illustrated and described, and other possible embodiments aredescribed. The figures are not necessarily drawn to scale, and in someinstances the drawings have been exaggerated and/or simplified in placesfor illustrative purposes only. One of ordinary skill in the art willappreciate the many possible applications and variations based on thefollowing examples of possible embodiments.

FIG. 1 illustrates an electrically driven vehicle 100 employing an audiosystem for generating synthetic engine and/or exhaust sounds accordingto the disclosure. In one embodiment, electrically powered vehicle 100includes a battery or battery pack 102, an electric drive motor 104 anda motor controller package 106. As used herein, an “electrically poweredvehicle” or “electrically driven vehicle” includes plug-in and hybridpassenger vehicles (e.g. not toys), having one or more electric motorsthat supply rotary power to the vehicle's wheels to propel the vehicleat highway speeds, for example up to 50 miles per hour and faster. Asillustrated, an electric drive motor 104 may be mounted adjacent therear 108 of the vehicle with battery pack 102 and motor controllerpackage 106 mounted in a compartment 110 above the electric drive motor.In other variations, battery pack 102, electric drive motor 104 andmotor controller package 106 may be mounted at alternative positions inthe vehicle 100, for example in the front of the vehicle or in amid-body motor configuration or at different locations in the vehicle.In other variations, vehicle 100 may include a manual or automatictransmission 105 for transmitting power from electric drive motor 104 toa drive shaft or axle of the vehicle. Motor controller 106 is connectedto operator controls generally designated 107 for energizing theelectric drive motor 104 and controlling the speed of the motor andvehicle 100.

Referring still to FIG. 1, in one embodiment, vehicle 100 is equippedwith one or more front speakers 112 and one or more rear speakers 114.Front speakers 112 may be mounted behind the grill 116 of vehicle 100 orin another location such that the front speakers project sound primarilyin a forward direction. Rear speakers 114 may be mounted at the rear 108of vehicle 100, for example behind the rear bumper, to project soundprimarily in a rearward direction. Speakers 112, 114 may be outwardlydirected and mounted outside of the passenger compartment 128 ofelectrically powered vehicle 100. Other speaker configurations arepossible, such as speakers mounted on the sides of vehicle 100. Speakers112, 114 may be mounted in an environmentally protected enclosure 118 toprotect the speakers from moisture and dirt. Speakers 112, 114 may berotatably mounted such that the position and direction of the speakersmay be adjusted manually or by means of an actuator 126 (one shown) suchas an electric stepper motor or linear actuator. In other embodiments,speakers 112, 114 may be configured for outside use, e.g., provided withwaterproof enclosures. Speakers 112 and 114 may be selected to have thesame or different frequency response characteristics. For example, frontspeakers 112 may have a mid-range frequency response or a full rangefrequency response to reproduce or simulate engine noise while rearspeakers 114 may have low-range frequency or full frequency responsecharacteristics to reproduce or simulate exhaust noise. Speakers 112,114 may be driven with an audio system generally designated 200 toreproduce or simulate engine and/or exhaust sounds.

Vehicle 100 may be provided with a first sensor 120 to monitor the speed(rpm) of electric drive motor 104. A second sensor 122 may be providedto monitor the speed of the vehicle (mph) based on wheel or axlerevolutions. A third sensor 124 may be provided to monitor the speed oroutput of transmission 105. The output of sensors 120, 122 and 124 maybe connected to audio system 200 to enable the system to adjust thefrequency, pitch or volume of engine and/or exhaust sounds reproduced orsimulated by audio system 200 based on the speed of electric drive motor104 and/or the vehicle speed. In other embodiments, sensors may beprovided to monitor the amperage or current load drawn by electric drivemotor 104 and the output of transmission 105.

FIG. 2 is a schematic representation of one embodiment of audio system200 and related components for simulating engine and/or exhaust sounds.In the illustrated embodiment, system 200 includes a processor 202 forcontrolling various functions of the audio system. Processor 202 isoperatively connected to an associated data and/or media storage unit204. Audio system 200 may also include a display 214 and a data entryfeature 216 such as a keyboard, touch screen or a voice recognitionfeature. In one embodiment, display 214, data entry feature 216 andcontrols such as switches or knobs 226 may be mounted in the dashboardof vehicle 100 or in another location accessible to the operator of thevehicle.

Audio system 200 may also include components such as pre-amplifier 222,amplifier 224 as well as other components such as a radio frequencyreceiver for receiving am and fm radio frequency transmissions, a mediaplayer such as a DVD or CD player, mixer(s), equalizer(s), volume, bassand treble controls and other components typically used in automotiveaudio systems. Audio system 200 may include a digital, analog oranalog/digital interface 228 for connecting processor 202 to one or moreof sensors 120, 122, 124 to provide an input reflecting a performanceparameter of vehicle 100 such as vehicle speed, acceleration, motorcurrent draw, transmission output or other similar parameter. System 200may further include one or more analog, digital or analog/digitalinterfaces 230 to connect processor 202 to data and/or media storageunit 204, cellular transceiver 206, preamplifier 222, amplifier 224,display 214, data entry feature 216 and controls such as switches orknobs 226.

Referring still to FIG. 2, processor 202 may be operatively connected toa cellular transceiver 206, which may be configured to transmit andreceive data, voice, and media transmissions over a wireless interface209 with cellular telephone network generally designated 208. In oneembodiment, cellular transceiver 206 may be permanently mounted invehicle 100. In other embodiments, cellular transceiver 206 may comprisea portable device such as a cellular handset, a personal computer oranother user device having hardware and software for communicating overa cellular network. The portable device may communicate with theprocessor via an interface such as a USB connector or a wirelessinterface. Cellular network 208 provides a communications link betweentransceiver 206 and a cellular telephone company 207, which may connecttransceiver to an Internet service provider 210.

Internet service provider 210 provides a communications link with athird party service provider 212 via a private or public network such asthe Internet 211. In other embodiments, third party service provider 212may be linked directly to cellular network 208. In one embodiment, thirdparty service provider 212 maintains a server 218 and an associateddatabase 220. As used herein, the term “server” refers to a computerthat delivers information and/or software to other devices via a privateor public network such as the Internet. In one embodiment, server 218may communicate with other devices using a protocol such as Hyper TextTransfer Protocol (http) which enables transmission of information inthe form of text documents coded in a standard markup language such asHyper Text Markup Language (HTML).

A plurality of pre-recorded engine and/or exhaust sounds, or algorithmsfor producing engine and exhaust sounds, may be stored on database 220.Wind sounds and road sounds generated by the tires of a vehicle may alsobe incorporated into stored vehicle sounds. Pre-recorded engine andexhaust sounds, wind sounds, road sounds (or algorithms for producingsuch sounds) associated with different types of vehicles and/or enginesmay be stored on database 220. For example, engine and exhaust soundsassociated with different types of sports cars, “muscle” cars, differenttypes of racing cars, turbine powered cars, jet engines and othervehicles, engines and exhaust systems may be recorded and stored ondatabase 220. Pre-recorded engine and exhaust sounds for individualvehicles may be stored on multiple tracks such that the pre-recordedengine and exhaust sounds may be individually accessed, processed andmanipulated to produce the desired results.

In one embodiment, a consumer may access cellular network 208 using dataentry feature 216 and cellular transceiver 206 to connect to third partyservice provider 212 via the cellular network 208 and Internet 211.Server 218 may respond by transmitting information enabling processor202 to display one or more preformatted screens with display 214. Thepreformatted screen or screens enable a consumer to select and purchaseprerecorded engine and/or exhaust sounds or an algorithm for producingsuch sounds.

FIG. 3 is an exemplary screen display 300 enabling a consumer or user topurchase and download engine and/or exhaust sounds for use withelectrically powered vehicles such as vehicle 100. As illustrated,screen display 300 lists a variety of engine and/or exhaust soundsassociated with different automobiles from which the consumer maychoose, for example, using data entry feature 216 to select the name 302of a particular vehicle or vehicle or engine type. The vehicle soundsmay be prerecorded actual sounds and/or algorithms for producing ormanipulating the sounds. After selecting the vehicle name or type theconsumer may use an engine/exhaust portion 304 of display 300 to selectthe engine sound associated with the vehicle, the exhaust soundassociated with the vehicle or both. The consumer may use display 300 toselect an engine sound associated with one type of vehicle and anexhaust sound associated with another type of vehicle. Screen display300 may also include selections for other sounds, or algorithms forsimulating sounds, such as road sounds, wind sounds, and sounds forfrightening or otherwise deterring animals from entering the path of avehicle.

Referring still to FIG. 3, in one embodiment, the consumer may select apreview function 306. When the customer selects preview function 306,server 218 may respond with a transmission including a segment of theselected vehicle engine or exhaust sound or algorithm. The transmittedpreview of the selected sound may be directed to speakers 112 and/or 114to enable the consumer to decide whether he or she wishes to purchasethe selected prerecorded engine or exhaust sounds or algorithm forreproducing the sound. The consumer may also select a combination ofsounds, e.g., an engine sound with, for example, one or more of anexhaust sound, road noise and wind sounds and/or an algorithm forproducing such sounds.

Referring to FIGS. 2 and 3, after the consumer has selected an engineand/or exhaust sound, server 218 may transmit a purchase price 308 forinclusion in display 300 if the purchase price has not already beendisplayed to the consumer. The consumer may then specify a paymentoption 310 such as a credit card or debit card. If the consumer has anaccount with third party service provider 212, the customer may enter anaccount number and/or password. After the consumer has entered theinformation necessary to complete payment to the third party serviceprovider 212, server 218 accesses the selected engine and/or exhaustsounds, or algorithm for producing the sounds, on database 220 andtransmits the sounds or algorithm(s) to processor 202 via the Internetand cellular network 208. The transmitted sounds or algorithm(s) maythen be stored on data and/or media storage unit 204.

Referring again to FIGS. 1 and 2, in one embodiment, when electric drivemotor 104 of vehicle 100 is energized, processor 202 accesses datastorage unit 204 to direct stored engine and/or exhaust sounds topre-amplifier 222. The output from pre-amplifier 222 is directed toamplifier 224 which powers speakers 112 and 114. In one embodiment,speakers 112 and 114 are on separate audio channels such that speakers112 reproduce engine sounds while speakers 114 reproduce exhaust sounds.In other embodiments, a digital or analog mixer or similar device may beused to separate signals to speakers 112, 114 such that engine soundsare generated by front speakers 112 and exhaust sounds are generated byrear speakers 114.

Turning to FIG. 4, in one embodiment, speakers 112 and 114 may becontrolled to output a base volume of sound “V1.” “V1” may be selectedto generate a sound level that is audible over a predetermined distance,for example fifty feet. In this manner, other drivers, pedestrians andpets would be alerted to the presence of vehicle 100 even if the vehiclewas stopped at a stop sign or red light. In other embodiments, speakers112 and 114 are not energized until vehicle 100 begins to move and arede-energized when the vehicle comes to a stop.

Referring to FIGS. 2 and 4, the power to speakers 112 and 114 may becontrolled with processor 202 such that the sound output of the speakersvaries with a vehicle performance parameter such as vehicle speed. Inone embodiment, processor 202 increases or decreases the power tospeakers 112, 114 to increase the engine and/or exhaust sounds generatedby the speakers proportionally with the speed of electric drive motor104 as measured with motion sensor 122 (FIG. 1) which measures wheel oraxle speed. Alternatively, processor 202 may control the power tospeakers 112, 114 based on an input from sensors 120 and/or 124 thatdetect the revolutions per minute of electric drive motor 104 or thepower output of transmission 105. In other embodiments, the power tospeakers 112, 114 may be increased or decreased proportional to theelectrical current draw of electric drive motor 104. Thus, asillustrated, the volume (dB) and frequency (Hz) of sound generated byspeakers 112 and/or 114 increases or decreases as the speed of thevehicle increases or the rpm of electric drive motor 104 increases. Inone embodiment, the volume of sound increases linearly with speed asillustrated by line 1. In other embodiments, the volume of soundincreases non-linearly as illustrated by lines 2 and 3. In still otherembodiments, the driver may select between different sounds vs. speedprofiles (e.g., lines 1, 2 or 3) by means of a selector switch (notshown) connected to processor 202. Processor 202 may use pre-programmedalgorithms or instructions stored on data storage unit 204 to vary thevolume and pitch of engine and/or exhaust sounds generated by speakers112, 114.

Referring to FIG. 5, the power to speakers 112, 114 may be controlled toincrease or decrease the volume of sound generated proportionally to thevehicle's acceleration. In one variation, the volume of sound may be alinear function of the vehicle's acceleration and or deceleration asindicated by line 4, or alternatively may be a non-linear function ofthe vehicle's acceleration or deceleration as illustrated by lines 5 and6. Further, the volume and pitch may be varied depending upon whetherthe vehicle is accelerating or decelerating to simulate the differentsounds generated by a conventionally fueled vehicle as it acceleratesversus when it decelerates. In still other embodiments, the driver mayselect between different sound vs. acceleration profiles (e.g., lines 4,5 or 6) by means of a selector switch (not shown) connected to processor202.

Referring to FIG. 6, the tone or pitch of the engine and/or exhaustsounds generated by speakers 112, 114 may vary linearly with the speedof vehicle 100, acceleration and deceleration of the vehicle, the speedof electric drive motor 104, the electric load of electric drive motor104, the output of transmission 105 or the position of a manual speedcontroller used by the driver. This effect may be linear as illustratedby line 7, or non-linear as illustrated by lines 8 and 9. In still otherembodiments, the driver may select between different pitch vs. speedprofiles (e.g., lines 7, 8 or 9) by means of a selector switch (notshown) connected to processor 202.

Turning to FIG. 7, as illustrated by lines 10 and 11, the volume, toneor pitch of engine and/or exhaust sounds created by speakers 112 and 114may be varied in a “stepped” fashion as a function of the speed oracceleration of vehicle 100 to simulate the sound of a conventionallyfueled vehicle as it is shifted, either manually or by means of anautomatic transmission. This effect may be accomplished with processor202 using pre-programmed logic and instructions resident on data storagedevice 204. For example, processor 202 may step the tone or pitch ofengine or exhaust sounds up or down when the vehicle reachespredetermined speeds such as 20, 30 and 40 miles per hour. In otherembodiments, processor 202 may step the tone or pitch of engine orexhaust sounds up or down based on the current draw of electric drivemotor 104 or the power output of transmission 105 to simulate the soundof a conventionally fueled vehicle as it is shifted, either manually orby means of an automatic transmission.

Turning to FIG. 8, in yet another variation, the volume and/or frequencyof sound generated by speakers 112, 114 may be pulsed or interrupted tocreate different audible effects as illustrated by line 12. The pulsingor interrupting effect may be accomplished with processor 202 usingpre-programmed logic resident on data storage device 204 to control thepower to speakers 112, 114. The pulsing or interrupting effect may beused, for example, to simulate the exhaust sounds of an idlingcombustion engine running at low revolutions per minute (rpm).

As will be appreciated, the sound parameters illustrated and describedin connection with FIGS. 4-8 may be combined and manipulated to producethe desired sound effects. One or more pre-recorded engine and/orexhaust sounds, pre-recorded wind and road noise stored on data storagedevice 204 may be manipulated or extrapolated by means of algorithms,preprogrammed logic and/or manual operator controls to simulate engineand exhaust sounds based on vehicle speed, acceleration, deceleration,motor load and other vehicle performance parameters. Pre-recorded engineand exhaust sounds, pre-recorded wind and road noise may be combined toproduce the desired sound effects.

FIG. 9 illustrates an operator control consol 900 for controlling audiosystem 200 of electrically powered vehicle 100. In one embodiment,control consol 900 includes manual controls 902 for turning the frontand rear speakers 112, 114 of vehicle 100 (FIG. 1) on and off,increasing or decreasing the volume of sounds generated by the speakersand controls for adjusting the base and treble of the speakers. Controls902 may include an auto setting wherein a controller or processor 904controls some or all of the audio settings including frequency andvolume based on pre-programmed instructions stored in an associated datastorage device 906 and/or the input from sensors such as sensors 120,122 and 124 of FIG. 1. Controller or processor 904 may be the same as,or separate from, processor 202 of FIG. 2.

Manual controls 902 may include residential and highway settings wherebythe operator of the vehicle may select pre-programmed sound parameterssuch as volume or frequency based on the location of vehicle 100. Forexample, the operator of vehicle 100 may wish to increase or decreasethe volume or frequency of sound generated by speakers 112, 114depending upon the environment. In a residential environment, theoperator of vehicle 100 may wish to increase the volume of soundproduced by front speakers 112 relative to rear speakers 114 to alertpedestrians and pets that the vehicle is approaching. Controls 902 maybe knobs, buttons, switches or be incorporated into a touch screen. Asillustrated, separate controls 902 may be provided for front and rearspeakers 112, 114.

Control consol 900 may include a display 910, which may be the same as,or separate from, display 214 of FIG. 2. Display 910 may be a touchscreen or be provided with keys or buttons 912. In one embodiment, whenaudio system 200 is turned on, display 910 may display one or moreselections 914 for engine, exhaust, wind and road sounds. Display 910may also display selections for sounds corresponding to differentvehicle types. The operator of vehicle 100 may use keys 912 to selectengine, exhaust, road and wind sounds as well as sounds corresponding todifferent types of vehicles. Processor or controller 904 accesses datastorage device 906 to retrieve the selected sounds which are thenreproduced with speakers 112, 114 as described in connection with FIG.2. In one embodiment, data storage device 906 is the same as datastorage device 204 of FIG. 2 and includes pre-recorded sounds oralgorithms for producing the sounds that have been purchased anddownloaded as described in connection with FIG. 3.

In one embodiment, control consol 900 may be permanently mounted at alocation in electrically powered vehicle 100 such as the vehicledashboard or a similar location readily accessible to the operator ofthe vehicle. In other embodiments, controls 902, and/or display 910 maybe incorporated in a hand-held wireless device which communicates withcontroller 904 via a wireless radio frequency interface.

FIG. 10 illustrates a method of providing engine and exhaust sounds tobe used with an electrically powered vehicle. Referring now to FIGS. 2and 10, the process begins at step 1000 when a consumer opens a call tothird party service provider 212 and is connected to server 218. At step1002, server 218 accesses database 220 and electronically transmitsdisplay information to processor 202. The transmitted displayinformation may be a web page and/or in the form of text documents codedin a standard markup language such as Hyper Text Markup Language (HTML)which are displayed on display 214. The transmitted display may be thesame as, or similar to, selection screen 300 of FIG. 3 and includesoptions allowing the consumer to select from a variety of soundsincluding engine sounds, exhaust sounds, road and wind noise and animaldeterrent sounds. Animal deterrent sounds may include high-frequencysounds or noises selected to deter animals from entering the path of thevehicle or moving out of the path of the vehicle. Such sounds aretypically inaudible to the human ear. The selection display or screenmay also include purchase price(s) for the various sounds.

After the consumer has made his or her selections and transmitted theselections to third party service provider 212, the transmittedselections are received with server 218 at step 1004. Server 218 mayprompt the consumer to determine if the consumer wishes to hear apreview of the selected sounds at step 1006. If the consumer respondswith a request for a preview, server 218 may transmit a brief segment orsegments of the selected pre-recorded sounds at step 1008 for review bythe consumer. The transmitted sound segment may be encrypted orotherwise protected to insure that it is not re-recorded or otherwisestored.

After listening to the sound preview, the consumer may be prompted atstep 1010 to confirm his or her selection(s). If the consumer fails toconfirm the selection, the process returns to step 1002 and a clearedselection screen is displayed. If the consumer confirms theselection(s), server 218 transmits a prompt for the consumer to enterpayment information. The payment information may include the consumer'sname and address, a credit or debit number or other information. If theconsumer has an account with the third party service provider 212, theinformation may be a password and the consumer's account number orsimilar identifying information.

After the consumer has transmitted the requested payment and/or accountinformation, the information is verified or confirmed at step 1014.Server 218 may open a connection to a bank, credit card processingcenter or another service provider and transmit the consumer's credit ordebit card number, name, address and any other information required forverification of the payment information. If the consumer has an accountwith third party service provider 212, server 218 may access database220 to verify the account information and store information regardingthe order for further processing such as debiting the consumer's accountand/or generating a bill.

If the payment information is not verified or confirmed at step 1016,the process returns to step 1002 and a cleared selection screen is againdisplayed. Alternatively, an error message may be transmitted to theconsumer. If the payment information is confirmed, server 218 accessesdatabase 220 to retrieve the selected prerecorded engine, exhaust orother sounds and/or algorithms for reproducing or manipulating thesounds. The selected sounds and/or algorithms are then transmitted tothe consumer at step 1018. At step 1020, server 218 may transmit aprompt to the consumer to determine if the consumer wishes to makeanother selection. If the consumer elects to make another selection atstep 1022, the process returns to step 1002 and a cleared selectionscreen is displayed. Alternatively, if the consumer does not wish tomake further selections, the process is terminated at step 1024 and theconnection between server 218 and processor 202 is closed.

FIG. 11 is a flowchart illustrating a method for producing engine,exhaust and other sounds with an electrically powered vehicle 100.Referring to FIGS. 2 and 11, the process begins at step 1100 when aconsumer uses cellular transceiver 206 to open a call to third partyservice provider 212 via wireless interface 209 with cellular network208, cellular telephone company 207 and Internet service provider 210.In some instances, cellular telephone company 207 and Internet serviceprovider 210 may be the same entity. In other instances, a customer mayopen a call directly to third party service provider 212 over thecellular network.

Referring still to FIG. 11, after the call has been opened, server 218may transmit display information such as selection screen 300, which isreceived by the customer at step 1102. The transmitted displayinformation may be a web page and/or in the form of text documents codedin a standard markup language such as Hyper Text Markup Language (HTML)which are displayed on display 214. The transmitted display may includeoptions allowing the consumer to select from a variety of soundsincluding engine sounds, exhaust sounds, road and wind noise and animaldeterrent sounds. The selection display or screen 300 may also includepurchase price(s) for the various sounds.

At step 1104, the customer may use the display information or selectionscreen 300 and data entry feature 216 to then select one or more soundsassociated with a conventionally fueled vehicle such as engine andexhaust sounds, wind sounds and road noise. In one embodiment, thecustomer may also elect to receive a preview of one or more selectedsounds at step 1106. If the customer elects to receive a preview of oneor more selected sounds, the preview is transmitted to the customer andthe customer may listen to the preview at step 1108. The preview may bein the form of a prerecorded sound, and/or an algorithm for producing ormanipulating a prerecorded sound.

At step 1110, the customer may confirm his or her wish to purchase theselected the sounds. If the customer declines to confirm a purchase ofthe selected sound or sounds, the process returns to step 1102 and acleared selection screen is received by the customer. If the customerconfirms purchase of the selected sounds, the customer may enter andtransmit payment and/or account information at step 1112. Assuming thatthe customer's payment information is accepted, the selected soundsand/or algorithms for producing, manipulating or enhancing such soundsare transmitted by server 218 and received by processor 202 at step1114. The prerecorded sounds, algorithms for producing, manipulating orenhancing such sounds may be stored on data and/or media storage unit204 at step 1116 and played with vehicle audio system 200 at step 1118.

Referring to FIGS. 2 and 11, at step 1120 a vehicle performanceparameter is sensed with a sensor such as sensors 120, 122 and 124 ofFIGS. 1 and 2. The vehicle performance parameters may include the speedof the vehicle 100, acceleration of the vehicle, deceleration of thevehicle, speed of the electric drive motor 104 and the electric currentdraw of the electric drive motor. An output of one or more of sensors120, 122, 124 or other sensor is input to processor 202 via an analog,digital or analog/digital interface 228. At step 1122 processor 202 mayuse stored algorithms or preprogrammed logic resident on storage unit204 to vary a sound parameter such as volume or frequency to vary thesounds generated by audio system 200 with changes in the sensed vehicleperformance parameters.

Although the methods described in connection with FIGS. 10 and 11 havebeen described in connection with the use of a visual display, it willbe appreciated that the methods may be practiced without such a display.For example, selection information may be in the form a pre-recordedaudio menu that enables a customer to select and/or preview selectedsounds and transmit payment information without the use of a display. Insome embodiments, a customer may open a call directly to third partyservice provider 212, listen to a prerecorded menu of sounds and makeselections using, for example a cellular handset. The cellular handsetmay be linked to processor 202 and/or data and/or media storage unit 204of FIG. 2 by means of an interface such as a USB connector or a wirelessinterface for downloading and storing engine, exhaust and otherprerecorded sounds and/or algorithms for producing, enhancing ormanipulating such sounds.

It will be appreciated by those skilled in the art having the benefit ofthis disclosure that these methods and apparatus for a vehicle audiosystem for producing synthetic sound provide significant advantages incomparison to earlier methods and apparatus. It should be understoodthat the drawings and detailed description herein are to be regarded inan illustrative rather than a restrictive manner, and are not intendedto be limiting to the particular forms and examples disclosed. On thecontrary, included are any further modifications, changes,rearrangements, substitutions, alternatives, design choices, andembodiments apparent to those of ordinary skill in the art, withoutdeparting from the spirit and scope hereof, as defined by the followingclaims. Thus, it is intended that the following claims be interpreted toembrace all such further modifications, changes, rearrangements,substitutions, alternatives, design choices, and embodiments.

1. An electrically powered passenger vehicle comprising: an electricdrive motor operatively coupled to one or more of the vehicle's wheelsfor rotating the vehicle's wheels to propel the vehicle; a battery packfor powering the electric drive motor; a controller for controlling thespeed of the vehicle; a sensor for monitoring a performance parameter ofthe vehicle; a data storage unit including one of pre-recorded enginesounds, pre-recorded exhaust sounds, or one or more algorithms forreproducing engine sounds and exhaust sounds; a processor for accessingthe data storage unit and retrieving one of pre-recorded engine sounds,pre-recorded exhaust sounds, or one or more algorithms for reproducingengine sounds and exhaust sounds; an amplifier operably connected to theprocessor for amplifying one of an engine sound or exhaust sound; atleast one speaker operably connected the amplifier for projecting one ofengine sounds or exhaust sounds outside the vehicle; and wherein theprocessor receives an input generated by the sensor and varies a soundparameter of one of engine sounds or exhaust sounds projected by thespeaker based on a performance parameter of the vehicle.
 2. Theelectrically powered passenger vehicle of claim 1 wherein theperformance parameters include one or more of the speed of the vehicle,acceleration of the vehicle, deceleration of the vehicle, speed of thedrive motor and electric current draw of the drive motor.
 3. Theelectrically powered passenger vehicle of claim 1 wherein the soundparameters include volume and frequency.
 4. The electrically poweredpassenger vehicle of claim 1 further comprising at least one speakeroriented toward a front end of the vehicle and at least one speakeroriented toward the rear end of the vehicle wherein the speaker orientedtoward the front of the vehicle is configured to project engine soundsoutwardly from the vehicle and the speaker oriented toward the rear ofthe vehicle is configured to project exhaust sounds outwardly from thevehicle.
 5. The electrically powered passenger vehicle of claim 1further comprising a cellular transceiver connected to the processorwhereby the processor can communicate with a third party serviceprovider to download one of pre-recorded engine sounds, pre-recordedexhaust sounds, or one or more algorithms for reproducing engine soundsand exhaust sounds.
 6. A method of providing prerecorded vehicleoperating sounds or algorithms for reproducing vehicle operating soundscomprising: receiving an electronic transmission from a user deviceoperated by a potential purchaser with a server connected to a public orprivate computer network; electronically transmitting selectioninformation to the user device with the server connected to a public orprivate network, the selection information identifying vehicle soundselections including engine or exhaust sounds; receiving an electronictransmission from the user device operated by the potential purchaserselecting one or more engine or exhaust sounds; electronicallytransmitting one of a segment of a prerecorded engine or exhaust soundor an algorithm for producing an engine or exhaust sound to the userdevice via the public or private network; receiving an electronictransmission from the user device confirming that the potentialpurchaser wishes to purchase one of a selected prerecorded engine orexhaust sounds or an algorithm for producing a selected engine orexhaust sound; and electronically transmitting one of the selectedprerecorded engine or exhaust sounds or an algorithm for producing aselected engine or exhaust sound to the user device.
 7. The method ofclaim 6 further comprising electronically transmitting a prompt to theuser device enabling the potential purchaser to select a payment type.8. The method of claim 7 further comprising receiving an electronictransmission from the user device indicating a selected payment type. 9.The method of claim 8 further comprising electronically transmitting arequest to a third party to confirm payment information received fromthe potential purchaser.
 10. The method of claim 6, wherein the userdevice is a cellular transceiver.
 11. The method of claim 6, wherein theselection information comprises a screen display.
 12. The method ofclaim 6 further comprising electronically transmitting screen displayinformation to the potential purchaser with the server connected to apublic or private network, the display information including soundselections including one or more of engine sounds, exhaust sounds, windsounds, road sounds and animal deterrent sounds for display on the userdevice.
 13. An audio system for an electrically powered vehicle, theelectrically powered vehicle having one or more vehicle performancesensors for sensing a vehicle performance parameter, the audio systemcomprising: a data storage unit including one of pre-recorded enginesounds, pre-recorded exhaust sounds, or one or more algorithms forreproducing engine sounds and exhaust sounds; a processor for accessingthe data storage unit and retrieving one of pre-recorded engine sounds,pre-recorded exhaust sounds, or one or more algorithms for reproducingengine sounds and exhaust sounds; an amplifier operably connected to theprocessor for amplifying one of an engine sound or exhaust sound; atleast one outwardly directed speaker mounted outside of the passengercompartment of the vehicle and operably connected to the amplifier forgenerating one of an engine or exhaust sound; an interface between theprocessor and the one or more vehicle performance sensors for sensing avehicle performance parameter, the interface configured to receive aninput from the one or more vehicle performance sensors and transmit itto the processor; and wherein the processor receives the input from atleast one vehicle performance sensor and varies a sound parameter of oneof engine sounds or exhaust sounds projected by the speaker based on aperformance parameter of the vehicle.
 14. The audio system of claim 13wherein the vehicle performance parameters include one or more of thespeed of the vehicle, acceleration of the vehicle, deceleration of thevehicle, speed of the drive motor and electric current draw of the drivemotor.
 15. The audio system of claim 13 wherein the sound parametersinclude volume and frequency.
 16. The audio system of claim 13 furthercomprising at least one speaker oriented toward a front end of thevehicle and at least one speaker oriented toward the rear end of thevehicle wherein the speaker oriented toward the front of the vehicle isconfigured to project engine sounds outwardly from the vehicle and thespeaker oriented toward the rear of the vehicle is configured to projectexhaust sounds outwardly from the vehicle.
 17. The audio system of claim13 further comprising a cellular transceiver connected to the processorwhereby the processor can communicate with a third party serviceprovider to download one of pre-recorded engine sounds, pre-recordedexhaust sounds, or one or more algorithms for reproducing engine soundsand exhaust sounds.
 18. A method of producing vehicle sounds associatedwith a combustion engine, comprising: receiving an electronictransmission from a third party service provider, the electronictransmission including selection information for at least one ofpre-recorded engine sounds, pre-recorded exhaust sounds, or one or morealgorithms for reproducing engine sounds and exhaust sounds;electronically transmitting a selection from at least one ofpre-recorded engine sounds, pre-recorded exhaust sounds, or one or morealgorithms for reproducing engine sounds and exhaust sounds;electronically transmitting payment information to the third partyservice provider; electronically receiving the one or more ofpre-recorded engine sounds, pre-recorded exhaust sounds, or one or morealgorithms for reproducing engine sounds and exhaust sounds; storing thetransmitted one or more of pre-recorded engine sounds, pre-recordedexhaust sounds, or one or more algorithms for reproducing engine soundsand exhaust sounds; accessing the stored one or more of pre-recordedengine sounds, pre-recorded exhaust sounds, or one or more algorithmsfor reproducing engine sounds and exhaust sounds using an audio systemof an electrically powered passenger vehicle to reproduce one or more ofan engine sound or exhaust sound; and producing an engine or exhaustsound with the audio system of an electrically powered passenger vehiclewherein the audio system receives an input generated by at least onevehicle performance parameter sensor and varies a sound parameter of oneof engine sounds or exhaust sounds produced by the audio system based onthe performance parameter of the vehicle.
 19. The method of claim 18wherein the performance parameters include one or more of the speed ofthe vehicle, acceleration of the vehicle, deceleration of the vehicle,speed of the drive motor and electric current draw of the drive motor.20. The method of claim 18 wherein the sound parameters include volumeand frequency.